A differential pressure transducer is a device that provides an output indicative of a difference between two input pressures. For example, when a first pressure P1 is applied to one face of a deflecting diaphragm and a second pressure P2 is applied to an opposite face of the diaphragm the resulting deflection is related to the difference in pressure (for example, P1−P2) and corresponding pressure differential can be determined from the deflection.
Differential pressure transducers are used in a variety of applications, including filtering, pumping, hydraulics, etc., where accurate pressure differential measurements are critical to the proper performance of the system. Often these applications involve media that can be corrosive to certain sensor components, diaphragms, etc. Such sensitive components are often isolated from the surrounding harsh environments by oil-filled regions in communication with input pressure ports, tubes, etc., so that incoming pressure can be transmitted through the pressure ports, through the tubes, to the oil-filled regions, and to respective diaphragms and associated components for measurement.
Current designs and manufacturing methods can work well for certain transducer assemblies that are used in relatively low pressure, static, and quasi-static applications. However, failures can frequently occur in transducers that are exposed to high-pressure environments and/or to large numbers of pressure cycles. Such failures can occur in the various ports, tubes, joints, interfaces, etc. of the transducer assembly, particularly when the associated connecting welds are done without the benefit of inspection for defects.